Mammography apparatus and method of pressurizing a breast

Abstract

Mammography apparatus comprising an x-ray source, a movable paddle and a detector, wherein the paddle and the detector are arranged to cooperate for pressurizing a breast so as to prepare for x-ray imaging of the breast, wherein the paddle connects to a paddle drive control system that drives the paddle towards the detector with a selected speed, wherein the paddle drive control system connects to a speed controller which provides the paddle drive control system a variating target setpoint that sets a rate at which the paddle drive control system drives the paddle towards the detector, wherein the apparatus comprises a contact area measurement device with which the contact area of the breast with the paddle and/or the detector is measurable, and that the speed controller is only operable for varying the target setpoint of the paddle drive control system when the contact area measurement device establishes that the said contact area surpasses a predefined first threshold value.

The invention claimed is: 
     
       1. Mammography apparatus comprising:
 an x-ray source; 
 a movable paddle; and 
 a detector; 
 wherein the paddle and the detector are arranged to cooperate for pressurizing a breast so as to prepare for x-ray imaging of the breast; 
 wherein the paddle connects to a paddle drive control system configured to drive the paddle towards the detector with a selected speed; 
 wherein the paddle drive control system connects to a speed controller which provides the paddle drive control system a variating target setpoint that sets a rate at which the paddle drive control system drives the paddle towards the detector; 
 wherein the apparatus further comprises a contact area measurement device with which the contact area of the breast with the paddle and/or the detector is measurable; and 
 wherein the speed controller is only operable for varying the target setpoint of the paddle drive control system when the contact area measurement device establishes that the said contact area surpasses a predefined first threshold value. 
 
     
     
       2. Mammography apparatus according to  claim 1 , wherein the speed controller establishes a target setpoint of the paddle drive control system so as to control the pressurization of the breast to gradually increase to an eventual target value for the pressure or force applied to the breast. 
     
     
       3. Mammography apparatus according to  claim 2 , wherein the target setpoint of the paddle drive control system is adjusted at a rate to cause the pressure applied to the breast to increase with an amount in the range of about 1-2 kPa per second. 
     
     
       4. Mammography apparatus according to  claim 2 , wherein the target setpoint of the paddle drive control system is adjusted at a rate to cause the pressure applied to the breast to increase in approximately 5-10 seconds to the eventual target value for the pressure or force applied to the breast. 
     
     
       5. Mammography apparatus according to  claim 1 , wherein an initial pressure or force applied to the breast is set at a predefined second threshold value, and that the speed controller is only operable for varying the target setpoint of the paddle drive control system when the pressure or force applied to the breast surpasses the predefined second threshold value. 
     
     
       6. Method for x-ray imaging of a breast with a mammography apparatus comprising:
 pressurizing a breast using a movable paddle and a detector, so as to prepare for x-ray imaging of the breast using an x-ray source, wherein the pressurization of the breast is executed at a variating rate; and 
 measuring the contact area of the breast with the paddle and/or with the detector, wherein the rate for the pressurization of the breast is only varied when it is established that the measured contact area of the breast with the paddle and/or with the detector surpasses a predefined first threshold value. 
 
     
     
       7. Method according to  claim 6 , wherein the pressurization of the breast is executed to gradually increase a pressure or force applied on the breast to an eventual target value for the pressure or force applied to the breast which will be present during x-ray imaging. 
     
     
       8. Method according to  claim 6 , wherein the pressure applied to the breast is provided to increase with an amount in the range of about 1-2 kPa per second. 
     
     
       9. Method according to  claim 7 , wherein the pressure applied to the breast is provided to increase in approximately 5-10 seconds to the eventual target value for the pressure or force applied to the breast.